A black Oklahoma man, whom family say was unarmed, was fatally shot by police who were investigating the slain man's stalled car in the middle of the street.

Terence Crutcher, 40, died at a Tulsa hospital on Friday night shortly after the violent confrontation, the Tulsa World reported.

Police said Crutcher’s SUV had been stalled at an intersection on Tulsa’s northeast side on Friday evening. Officers en route to an unrelated call pulled over to investigate the vehicle around 7:40 p.m.

Crutcher's twin sister, Tiffany, told the Daily News her brother had just begun studying music appreciation at Tulsa Community College and had just left class when his car broke down. Crutcher's car had been in the shop recently and "was having some problems," she told The News.

Crutcher approached the responding officers on foot and failed to put his hands up when the cops ordered him to, police said.

Tiffany Crutcher said she believed her twin brother, Terence, was not armed when he was fatally shot by a Tulsa, Okla., cop late Friday.

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"He refused to follow commands given by the officers," Tulsa police spokeswoman Jeanne MacKenzie told the Associated Press. "They continued to talk to him, he continued not to listen and follow any commands."

When Crutcher reached into the stalled car in the middle of the north Tulsa road, one of the officers fired his Taser gun. Shortly after, a second officer fired a single gunshot at the man, MacKenzie said.

Crutcher immediately dropped to the ground and was rushed to the St. John Medical Center, where he later died.

The police officer who fired the fatal gunshot has been put on leave, as is routine in cases of police-involved shootings, MacKenzie said. The county district attorney will investigate whether the shooting was justified.

A Tulsa police officer shot and killed Crutcher after he ignored repeated requests to put up his hands before reaching into an SUV that was stalled in the middle of a street, authorities said.

(JOEY JOHNSON/AP Photo)

Police have not revealed whether Crutcher had a gun on him at the time of the shooting, but his sister told Tulsa World that she is certain he was unarmed.

“One fact I do know is that my brother was unarmed,” she said. She told The News Crutcher was a father to four children and "was very excited" about starting his new college program.

Online court records show that Crutcher pleaded no contest in 1996 to carrying a concealed weapon and resisting an officer and was given a six-month suspended sentence.

An attorney for the family has demanded the Tulsa police department “immediately” release any video footage of the shooting. Police said they believe a dashcam would have captured the confrontation.

The slain 40-year-old (center) was the father to four children.

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"All we want is for the police to be transparent in their investigation and provide the video we know does exist,” attorney Damario Solomon-Simmons told the News. "We want to know exactly what happened and go from there."

Solomon-Simmons is representing the family along with Melvin C. Hall and civil rights attorney Benjamin Crump, who has represented the families of Trayvon Martin and Michael Brown.

Solomon-Simmons called the killing "an extremely sad and serious situation as Terence was a beloved father, brother, son and friend."

According to a Guardian investigation into police-involved shootings in the U.S., Oklahoma cops kill people at a higher rate per capita than any other state.